BR122015021746A2 - method of decoding video data - Google Patents

Abstract

method of decoding video data a method of encoding video data includes: dividing a current image into at least one maximum encoding unit; determining an encoded depth to produce an encoding result by encoding at least a region divided from at least one maximum encoding unit according to the mode of operation of the encoding tool, respectively, based on a relationship between a depth of the hair at least one coding unit of at least one maximum coding unit, a coding tool and an operating mode; and outputting a bit stream including encoded video data of the encoded depth, information pertaining to an encoded depth of at least one maximum encoding unit, information pertaining to an encoding mode and information pertaining to the relationship.

Description

METHOD OF DECODING VIDEO DATA

Divided from BR 11 2012 009178-6 of 10/22/2010

TECHNICAL FIELD [0001] Devices and methods consistent with the exemplary modalities refer to the encoding and decoding of a video.

FUNDAMENTALS OF THE TECHNIQUE [0002] As hardware to reproduce and store high-resolution or high-quality video content is being developed and provided, the need for a video codec to efficiently encode and decode high-quality video content resolution and high quality is increasing. In a conventional video codec, a video is encoded according to a limited encoding method based on a macroblock having a predetermined size.

Disclosure of the Invention

Technical Problem [0003] One or more exemplary modalities provide a method and apparatus for encoding a video and a method and apparatus for decoding a video in a mode of operation of an encoding tool that varies according to the size of a unit of structured, hierarchical coding.

Problem Solution [0004] In accordance with one aspect of an exemplary embodiment, a method of encoding video data is provided, the method including: dividing a current image of the video data into at least one maximum encoding unit; determine a coded depth to produce a result of

2/93 final coding by coding at least one region divided from at least one maximum coding unit according to at least one mode of operation of at least one coding tool, respectively, based on a relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and a mode of operation, in which at least one divided region is generated by dividing hierarchically the at least one maximum coding unit of according to the depths; and producing a bit stream including encoded video data of the encoded depth, information regarding an encoded depth of at least one maximum encoding unit, information regarding an encoding mode, and information regarding the relationship between the depth of the at least at least one coding unit of at least one maximum coding unit, the coding tool, and the mode of operation in at least one maximum coding unit, where the coding unit can be characterized by a maximum size and depth, depth denotes a number of times that a coding unit is divided hierarchically, and as the depth deepens, deeper coding units according to depths can be divided from the maximum coding unit to obtain units of minimal coding, where the depth is deepened from an upper depth to a lower depth, in which as the depth deepens, the number of times the maximum coding unit is divided increases, and a total number of possible times when

3/93 the maximum coding unit is divided to a maximum depth and the maximum size and maximum depth of the coding unit can be predetermined. An operating mode of a coding tool for a coding unit is determined according to a depth of the coding unit.

Advantageous Effects of the Invention [0005] The video encoding apparatus according to exemplary modalities can determine a depth of an encoding unit and a mode of operation of an encoding tool according to the characteristics of the image data in order to increase a coding efficiency and coding information with reference to a relationship between the depth of the coding unit, the coding tool, and the mode of operation. Additionally, a video decoding device according to exemplary modalities can reconstruct the original image by decoding a received bit stream, based on information related to the relationship between the depth of the encoding unit, the encoding tool and the mode of operation. Consequently, the video encoding apparatus according to exemplary modalities and the video decoding apparatus according to exemplary modalities can effectively encode and decode a large amount of image data, such as a high resolution or high quality image, respectively.

Brief Description of the Drawings [0006] The aspects mentioned above and / or others will become more evident through a detailed description of the modalities

4/93 copies with reference to the accompanying drawings in which:

Figure 1 is a block diagram of a video encoding device, according to an exemplary embodiment;

Figure 2 is a block diagram of a video decoding device, according to an exemplary embodiment;

Figure 3 is a diagram for describing a concept of coding units according to an exemplary embodiment;

Figure 4 is a block diagram of an image encoder based on the coding units according to an exemplary embodiment;

Figure 5 is a block diagram of an image decoder based on the coding units according to an exemplary embodiment;

Figure 6 is a diagram illustrating units of deeper coding according to depths, and partitions according to an exemplary modality;

Figure 7 is a diagram for describing a relationship between a coding unit and transformation units, according to an exemplary embodiment;

Figure 8 is a diagram for describing coding information of the coding units corresponding to a coded depth, according to an exemplary embodiment;

Figure 9 is a diagram of deeper coding units according to depths, according to an exemplary embodiment;

Figures 10 to 12 are diagrams to describe a relationship between coding units, prediction units, and transformation units according to a

5/93 exemplary modality;

Figure 13 is a diagram to describe a relationship between a coding unit, a prediction unit or a partition, and a transformation unit, according to the exemplary coding mode information in Table 1, below, according to a modality exemplary;

Figure 14 is a flow chart illustrating a method of encoding a video, according to an exemplary embodiment; and

Figure 15 is a flow chart illustrating a method of decoding a video, according to an exemplary modality.

Figure 16 is a block diagram of a video encoding device based on an encoding tool considering the size of an encoding unit, according to an exemplary embodiment;

Figure 17 is a diagram of appliance blocks in video decoding based in a tool in coding considering the size of a unity in

coding, according to an exemplary modality;

Figure 18 is a diagram for describing a relationship between the size of a coding unit, a coding tool, and a mode of operation, according to an exemplary embodiment;

Figure 19 is a diagram for describing a relationship between a depth of a coding unit, a coding tool, and a mode of operation, according to an exemplary embodiment;

Figure 20 is a diagram to describe a relationship between a depth of a coding unit, a coding tool, and a mode of operation, according to an exemplary embodiment;

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Figure 21 illustrates the syntax of a set of sequence parameters, in which information related to a relationship between a depth of a coding unit, a coding tool, and an operating mode is inserted, according to an exemplary mode;

Figure 22 is a flow chart illustrating a video encoding method based on an encoding tool considering the size of an encoding unit, according to an exemplary modality; and

Figure 23 is a flow chart illustrating a method of

decoding of video with based on a tool in coding considering O size of a unit in coding, according an modality exemplary.

Best Mode for Carrying Out the Invention [0007] In accordance with an aspect of an exemplary embodiment, a method of encoding video data is provided, the method including: dividing a current image of the video data into at least one maximum encoding unit; determine a coded depth to produce a final coding result by coding at least one region divided from at least one maximum coding unit according to at least one mode of operation of at least one coding tool, respectively, based on a relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and a mode of operation, in which at least one divided region is generated by dividing hierarchically at least a maximum coding unit according to the depths; and produce a bit stream including video data

7/93 encoded from the encoded depth, information regarding an encoded depth of at least one maximum encoding unit, information regarding an encoding mode, and information regarding the relationship between the depth of at least one encoding unit of action at least one maximum coding unit, the coding tool, and the mode of operation in at least one maximum coding unit, where the coding unit can be characterized by a maximum size and a depth, the depth denotes a number of times where a coding unit is divided hierarchically, and as the depth deepens, deeper coding units according to depths can be divided from the maximum coding unit to obtain minimum coding units, where the depth is deepened from a higher depth to a depth i lower, where as the depth deepens, a number of times the maximum coding unit is divided increases, and the total number of possible times the maximum coding unit is divided corresponds to a maximum depth and in that the maximum size and maximum depth of the encoding unit can be predetermined. An operating mode of a coding tool for a coding unit is determined according to a depth of the coding unit.

[0008] Information regarding the relationship between the depth of at least one coding unit and at least one maximum coding unit, the coding tool and the mode of operation can be pre-established in slice units, frame units, or units of

8/93 frame of the current image.

[0009] The at least one coding tool for the coding of at least one maximum coding unit can include at least one of quantization, transformation, intra-prediction, inter-prediction, motion compensation, entropy coding and loop filtration .

[00010] If the coding tool, an operating mode of which is determined according to a depth of the coding unit, is intra-prediction, the operating mode can include at least one intra-prediction mode, classified according to with a number of intra-prediction directions or can include an intra-prediction mode to smooth regions in the coding units corresponding to the depths of an intra-prediction mode to retain a boundary line.

[00011] If the coding tool, an operating mode from which it is determined according to a depth of the coding unit, is inter-prediction, the operating mode can include an inter-prediction mode according to at least one method of determining a motion vector.

[00012] If the coding tool, a mode of operation from which it is determined according to a depth of the coding unit, is transformation, the mode of operation can include at least one transformation mode classified according to an index of one rotational transformation matrix.

[00013] If the coding tool, a mode of operation of which is determined according to a depth of a coding unit, is quantization, the mode of operation may include at least one quantization mode classified according to the fact that whether a delta quantization parameter should

9/93 be used.

[00014] In accordance with an aspect of another exemplary embodiment, a method of decoding video data is provided, the method including: receiving and analyzing a bit stream including encoded video data; extract, from the bit stream, the encoded video data, information regarding an encoded depth of at least one maximum encoding unit, information regarding an encoding mode, and information regarding an interface between a depth at least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode; and decoding the encoded video data in at least one maximum encoding unit according to an encoding tool operating mode equating an encoding unit corresponding to at least one encoded depth, based on information related to the encoded depth of the at least at least one maximum coding unit, information regarding the coding mode, and information regarding the relationship between the depth of at least one coding unit of at least one maximum coding unit, the coding tool, and the mode operating mode, in which the mode of operation of the coding tool for a coding unit is determined according to the coded depth of the coding unit.

[00015] Ά information regarding the relationship between the depth of at least one coding unit and at least one maximum coding unit, coding tool and mode of operation can be extracted in slice units, frame units, or sequence units of frames from

10/93 current image.

[00016] The coding tool for the coding of at least one maximum coding unit can include at least quantization, transformation, intra-prediction, interpretation, motion compensation, entropy coding and loop filtering, in which data decoding Encoded video can include performing a decoding tool corresponding to the encoding tool for encoding at least one maximum encoding unit. [00017] In accordance with an aspect of another exemplary embodiment, an apparatus is provided for encoding video data, the apparatus including: an encoding unit divider that divides a current image of the video data into at least one maximum encoding unit ; a coding unit determiner that determines a coded depth to produce a final coding result by coding at least a region divided from at least one maximum coding unit according to at least one mode and operation of at least one coding tool , respectively, based on a relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool and an operating mode, in which at least one divided region is generated by means of hierarchically divide at least one maximum coding unit according to depths; and an output unit that produces a bit stream including encoded video data that is the result of final encoding, information with respect to an encoded depth of at least one maximum encoding unit, information with respect to a

11/93 coding mode, and information regarding the relationship between the depth of at least one coding unit of at least one maximum coding unit, the coding tool, and the mode of operation on at least one maximum coding unit . An operating mode of a coding tool for a coding unit is determined according to a depth of the coding unit.

[00018] In accordance with an aspect of another exemplary embodiment, an apparatus is provided for decoding video data, the apparatus including: a receiver receiving and analyzing a bit stream including encoded video data; an extractor that extracts the encoded video data from the bit stream, information related to an encoded depth of at least one maximum encoding unit, information regarding an encoding mode, information regarding the relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode; and a decoder that decodes the encoded video data in at least one maximum encoding unit according to a mode of operation of an encoding tool equating an encoding unit corresponding to at least one encoded depth, based on depth-related information encoded from at least one maximum encoding unit, information regarding the encoding mode, and information regarding the relationship between the depth of at least one encoding unit and at least one maximum encoding unit, encoding tool, and operating mode, where the operating tool operation mode

12/93 coding for a coding unit is determined according to the coded depth of the coding unit.

[00019] In accordance with an aspect of another exemplary embodiment, a method of decoding video data is provided, the method including: decoding the video data encoded in at least one maximum encoding unit according to a mode of operation of a coding tool matching a coding unit corresponding to at least one coded depth, based on information related to a coded depth of at least one maximum coding unit, information related to a coding mode, and information related to a relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode, wherein the operating mode of the coding tool for a coding unit is determined according to the depth coded from the coding unit.

[00020] In accordance with an aspect of another embodiment, a computer-readable recording medium is provided, having recorded in it a program to execute the method of encoding video data.

[00021] According to another aspect of another exemplary modality, a computer-readable recording medium is provided which has a program recorded in it to perform the method of decoding video data.

Mode for the Invention [00022] In the following, exemplary modalities will be described more fully with reference to the accompanying drawings.

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In addition, expressions such as at least one of, when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. In exemplary modalities, a unit may or may not refer to a size unit, depending on its context. Specifically, video encoding and decoding performed based on spatially hierarchical data units according to one or more exemplary modalities will be described with reference to Figures 1 to 15. In addition, video encoding and decoding performed in an operating mode of a coding tool that varies according to the size of a coding unit according to one or more exemplary modalities will be described with reference to Figures 16 to 23.

[00023] In the following exemplary embodiments, an encoding unit refers to either an encoding data unit in which the image data is encoded by the side of an encoder or an encoded data unit in which the encoded image data is decoded from the decoder side. In addition, a coded depth refers to a depth at which a coding unit is coded. Then, an image can also denote an image for a video or a mobile image, that is, the video itself.

[00024] An apparatus and method for encoding a video and an apparatus and method for decoding a video according to exemplary modalities will now be described with reference to Figures 1 to 15.

[00025] Figure 1 is a block diagram of a video encoding device 100, according to a modality

Exemplary 14/93. Referring to Figure 1, the video coding apparatus 100 includes a maximum coding unit divider 110, a coding unit determiner 120, and an output unit 130.

[00026] The maximum coding unit divider 110 can divide a current image based on a maximum coding unit for the current frame of an image. The current frame is larger than the maximum encoding unit, the image data of the current frame can be divided into at least one maximum encoding unit. The maximum coding unit according to an exemplary embodiment can be a data unit having a size of 32x32, 64x64, 128x128, 256x256, etc., wherein a format of the data unit is a square having a width and height in squares of 2. The image data can be output to the coding unit determinator 120 according to at least one maximum coding unit.

[00027] A coding unit according to an exemplary mode can be characterized by a maximum size and depth. Depth denotes a number of times that the coding unit is spatially divided from the maximum coding unit and, as the depth is deepened or increased, deeper coding units, according to the depths, can be divided from the maximum coding unit to a minimum coding unit. A maximum coding depth is a higher depth and a minimum coding depth is a lower depth. As the size of a coding unit corresponding to each depth decreases to the

As the depth of the maximum coding unit is deepened, a coding unit corresponding to a higher depth may include a plurality of coding units corresponding to the lower depths.

[00028] As described above, the image data of the current frame is divided into the maximum encoding units according to a maximum encoding unit size, and each of the maximum encoding units can include deeper encoding units that are divided according to the depths. As the maximum coding unit according to an exemplary modality is divided according to the depths, the image data of a spatial domain included in the maximum coding unit can be classified hierarchically according to the depths.

[00029] A maximum depth and a maximum size of a coding unit, which limit the total number of times the height and width of the maximum coding unit are divided hierarchically, can be predetermined.

[00030] The coding unit determinator 120 encodes at least one divided region obtained by dividing a region of the maximum coding unit according to the depths, and determines a depth to output the finally encoded image data according to the at least least one divided region. In other words, the encoding unit determiner 120 determines an encoded depth by encoding the image data in the deepest encoding units according to the depths, in accordance with the maximum encoding unit of the current frame, and selects a depth having O

16/93 minor coding error. Thus, the coded image data from the coding unit corresponding to the determined coded depth is finally produced. In addition, coding units corresponding to the coded depth can be considered as coded coding units.

[00031] The determined coded depth and the image data encoded according to the determined coded depth are output to output unit 130.

[00032] The image data in the maximum encoding unit is encoded based on the deepest encoding units corresponding to at least a depth equal to or below the maximum depth, and the results of encoding the image data are compared based on each one of the deepest coding units. A depth having the smallest coding error can be selected after comparing the coding errors of the deepest coding units. At least one coded depth can be selected for each maximum coding unit.

[00033] The size of the maximum coding unit is divided since a coding unit is divided hierarchically according to depths, and as the number of coding units increases. In addition, even if the coding units correspond to the same depth in a maximum coding unit, it is determined whether to divide each of the coding units corresponding to the same depth to a lower depth by decreasing a coding error of the image data of each coding unit separately.

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Consequently, even when the image data is included in a maximum coding unit, the image data is divided into regions according to depths and coding errors can differ according to the regions in that maximum coding unit, and so the coded depths may differ according to the regions in the image data. Thus, one or more coded depths can be determined in a unit of

coding maximum, and the image data gives unity in coding maximum can to be divided from a deal with at units of coding in at least one depth coded. [00034] Consequently, O determiner in unity in coding 120 can to determine the units of coding what

have a tree structure included in the maximum coding unit. Coding units having a tree structure according to an exemplary embodiment include coding units corresponding to a depth determined to be the coded depth, from all the deepest coding units included in the maximum coding unit. A coding unit of a coded depth can be determined hierarchically according to the depths in the same region as the maximum coding unit, and can be determined independently in different regions. Similarly, a coded depth in one current region can be determined independently of a coded depth in another region.

[00035] A maximum depth according to an exemplary modality is an index related to the number of times of division

18/93 from a maximum coding unit to a minimum coding unit. A first maximum depth according to an exemplary embodiment can denote the total number of times of division from the maximum coding unit to the minimum coding unit. A second maximum depth according to an exemplary embodiment can denote the total number of depth levels from the maximum coding unit to the minimum coding unit. For example, when the depth of the maximum coding unit is zero, a depth of a coding unit, in which the maximum coding unit is divided once, can be set to 1, and a depth of a coding unit; in which the maximum coding unit is divided twice; can be set to 2. Here, if the minimum coding unit is a coding unit in which the maximum coding unit is divided four times, there are 5 levels of depth, depth 0, 1, 2, 3 and 4, and so the first maximum depth can be set to 4, and the second maximum depth can be set to 5.

[00036] Prediction coding and transformation can be performed according to the maximum coding unit. Prediction coding and transformation are also performed based on the deepest coding units according to a depth equal to, or depths less than the maximum depth, according to the maximum coding unit. The transformation can be performed according to an orthogonal transformation or integer transformation method.

[00037] As the number of coding units most

19/93 deep increases whenever the maximum coding unit is divided according to depths; coding including prediction coding and transformation is performed on all units and deeper coding generated as the depth is deepened. For convenience of description, prediction coding and transformation will now be described based on a coding unit of a current depth, in a maximum coding unit.

[00038] The video encoding apparatus 100 can variablely select a size or format of a data unit to encode the image data. To encode image data, operations such as prediction, transformation, and entropy coding are performed and at that time, the same data unit can be used for all operations or different data units can be used for each operation .

[00039] For example, video encoding apparatus 100 may select not only an encoding unit to encode the image, but also a data unit other than the encoding unit in order to perform prediction encoding on the image data in the encoding unit.

[00040] To perform prediction coding in the maximum coding unit, prediction coding can be carried out based on a coding unit corresponding to a coded depth, that is, based on a coding unit that is no longer divided into a coding unit corresponding to a lower depth. Then, the encoding unit that is no longer divided and becomes a base unit for encoding

20/93 prediction will now be referred to as a prediction unit. A partition obtained by dividing the prediction unit can include a prediction unit or a data unit obtained by dividing at least one of a height and a width of the prediction unit.

[00041] For example, when a 2Nx2N encoding unit (where N is a positive integer) is no longer divided and becomes a 2Nx2N prediction unit, and a partition size can be 2Nx2N, 2NxN, Nx2N, or NxN. Examples of a partition type include symmetric partitions that are obtained simply by dividing a height or width of the prediction unit, partitions obtained by asymmetrically dividing the height or width of the prediction unit, such as l: n or n: l, partitions which are obtained by geometric division of the prediction unit, and partitions that have arbitrary shapes.

[00042] A prediction mode of the prediction unit can be at least one of: an intra-mode, an inter-mode, and a jump mode. For example, the intra-mode or the inter-mode can be performed on the 2Nx2N, 2NxN, Nx2N, or NxN partition. In addition, the jump mode can only be performed on the 2Nx2N partition. Coding is performed independently in a prediction unit in an encoding unit, thereby selecting a prediction mode that has the least coding error.

[00043] The video coding apparatus 100 can also perform the transformation in the image data into a coding unit based not only on the coding unit to encode the image data, but also based on the data unit which is different encoding unit.

21/93 [00044] To perform the transformation on the coding unit, the transformation can be performed on the basis of a data unit that has a size less than or equal to that of the coding unit. For example, the data unit for the transformation can include a data unit for an intra-mode and a data unit for an inter-mode.

[00045] A data unit used as a basis for the transformation will now be referred to as a transformation unit. A transformation depth indicating the number of dividing times to reach the transformation unit by dividing the height and width of the coding unit can be adjusted in the transformation unit. For example, in a current coding unit of 2Nx2N, a transformation depth can be 0 when the size of a transformation unit is also 2Nx2N, it can be 1 when each of the height and width of the current coding unit is divided into two equal parts, totally divided into 4 ^Λ 2 transformation units, and the size of the transformation unit is thus NxN, and can be 2 when each of the height and width of the current coding unit is divided into four equal parts, divided entirely into 4 ^Λ 1 transformation units and the size of the transformation units is thus N / 2xN / 2. For example, the transformation unit can be adjusted according to a hierarchical tree structure, in which a transformation unit, of a higher transformation depth, is divided into four transformation units of a lower transformation depth, according to the hierarchical characteristics of a depth of transformation.

[00046] Similar to the coding unit, the coding unit

22/93 transformation in the coding unit can be recursively divided into smaller regions, so that the transformation unit can be determined independently into region units. Thus, the residual data in the coding unit can be divided according to the transformation having the tree structure according to the transformation depths.

[00047] Coding information according to the coding units corresponding to a coded depth requires not only information about the coded depth, but also about information related to the prediction and transformation coding. Consequently, the coding unit determiner 120 not only determines a coded depth having a lower coding error, but also determines a partition type in a prediction unit, a prediction mode according to the prediction units, and a size of a transformation unit for transformation.

[00048] Coding units according to a tree structure in a maximum coding unit and a method of determining a partition, according to exemplary modalities, will be described in detail later with reference to figures 3 to 12.

[00049] The coding unit determinator 120 can measure a coding error of deeper coding units according to the depths using Rate-Distortion Optimization based on Lagrangian multipliers.

[00050] Output unit 130 outputs the image data from the maximum encoding unit, which is encoded with

23/93 base on the smallest coded depth determined by the coding unit determiner 120, and information on the coding mode according to the coded depth, in bit streams.

[00051] The encoded image data can be obtained by encoding the residual data of an image.

[00052] Information about the encoding mode according to the encoded depth can include information about the encoded depth, the type of partition in the prediction unit, the prediction mode, and the size of the transformation unit.

[00053] The information about the coded depth can be defined using division information according to the depths, which indicates whether the coding is performed in coding units of a lower depth instead of a current depth. If the current depth of the current coding unit is the coded depth, the image data in the current coding unit is encoded and output, and so the split information can be set not to divide the current coding unit to a lower depth. Alternatively, if the current depth of the current coding unit is not the coded depth, coding is performed in the coding unit of the lowest depth, and so the splitting information can be set to divide the current coding unit to obtain the units coding the lowest depth.

[00054] If the current depth is not the coded depth, the coding is performed in the coding unit which is divided into the coding unit of the

24/93 lower depth. Since there is at least one lowest depth coding unit in a current depth coding unit, coding is performed repeatedly on each lowest depth coding unit, and so coding can be performed recursively for the coding that have the same depth.

[00055] As the coding units having a tree structure are determined for a maximum coding unit, and information about at least one coding mode is determined for a coding unit of a coded depth, information about at least one coding mode. encoding can be determined for a maximum encoding unit. In addition, an encoded depth of the image data of the maximum encoding unit can be different according to the locations since the image data is divided hierarchically according to the depths, and thus the information about the encoded depth and the mode encoding can be adjusted for the image data.

[00056] Consequently, output unit 130 can assign encoding information about a corresponding encoded depth and an encoding mode to at least one of the encoding unit, prediction unit, and a minimum unit included in the maximum encoding unit.

[00057] The minimum unit according to an exemplary modality is a rectangular data unit obtained by dividing by 4 the minimum coding unit constituting the lowest depth. Alternatively, the minimum unit can be a maximum rectangular data unit that can be

25/93 included in all coding units, prediction units, partition units, and transformation units included in the maximum coding unit.

[00058] For example, the coding information emitted through the output unit 130 can be classified into coding information according to the coding units, and coding information according to the prediction units. The encoding information according to the encoding units can include information about the prediction mode and the size of the partitions. The coding information according to the prediction units can include information about an estimated direction of an inter-mode, about a reference image index of the inter-mode, about a motion vector, about a chroma component of an intra-mode. mode, and on an intra-mode interpolation method. In addition, information about a maximum coding unit size defined according to the illustrations, slices, or GOPs, and information about a maximum depth can be entered in SPS (Sequence Parameter Set) or a bitstream header .

[00059] In the video coding apparatus 100, the deepest coding unit can be a coding unit obtained by dividing a height or width of a coding unit of a higher depth, which is one layer above, by two. In other words, when the size of the current depth coding unit is 2Nx2N, the size of the bottom depth coding unit is NxN. In addition, the current depth coding unit having the size of 2Nx2N can include a maximum of 4 of the lower depth coding units.

26/93 [00060] Consequently, the video encoding apparatus 100 can form the encoding units having the tree structure by determining the encoding units having an optimal size and an optimal size for each maximum encoding unit, based on the size of the maximum coding unit and the maximum depth determined considering the characteristics of the current frame. In addition, since coding can be performed on each maximum coding unit using any of the various prediction and transformation modes, an optimal coding mode can be determined by considering the characteristics of the coding unit of various image sizes.

[00061] Thus, if an image having high resolution or a large amount of data is encoded in a conventional macroblock, a number of macroblocks per frame increases excessively. Consequently, a number of pieces of compressed information generated for each macroblock increases, thus making it difficult to transmit the compressed information and decreasing the efficiency of data compression. However, by using the video coding apparatus 100, the image compression efficiency can be increased once a coding unit is adjusted while considering the characteristics of an image while increasing a maximum size of a coding unit while considering a image size.

[00062] Figure 2 is a block diagram of a 200 video decoding equipment, according to an exemplary modality. With reference to fig. 2, the video decoding equipment 200 includes a receiver 210, an encoder information and image data extractor 220, and a

27/93 image data decoder 230. Definitions of the various terms, such as an encoding unit, a depth, a prediction unit, a transformation unit, and information on various encoding modes, for various operations of the decoding equipment 200 are identical to those described with reference to Figure 1.

[00063] Receiver 210 receives and analyzes a bit stream from an encoded video. The coder information and image data extractor 220 extracts the coded image data for each coding unit from the bit stream analyzed, wherein the coding units have a tree structure according to each maximum coding unit, and output the extracted image data to the image data decoder 230. The coding information and image data extractor 220 can extract information about a maximum size of an encoding unit from a current frame, from a header on the current frame or SPS.

[00064] Furthermore, the coding information and image data extractor 220 extracts information about a coded depth and a coding mode for the coding units having a tree structure according to each maximum coding unit, from the bit stream analyzed. The information extracted about the encoded depth and the encoding mode is output to the image data decoder 230. That is, the image data in a bit stream is divided into the maximum encoding unit so that the decoder of image data 230 decodes the image data for each maximum encoding unit.

[00065] Information about the coded depth and the mode

28/93 coding according to the maximum coding unit can be adjusted for information about at least one coding unit corresponding to the coded depth, and information about a coding mode can include information about a partition type of a coding unit corresponding, corresponding to the coded depth, on a prediction mode, and a size of the transformation unit. In addition, division information according to depths can be extracted as information about the coded depth.

[00066] The information about the coded depth and the coding mode according to each maximum coding unit extracted by the image data and coding information extractor 220 is information about a coded depth and a coding mode determined to generate an error minimum encoding when an encoder, such as video encoding apparatus 100, repeatedly encodes for each deepest encoding unit according to the depths according to each maximum encoding unit. Consequently, the video decoding equipment 200 can restore an image by decoding the image data according to an encoded depth and an encoding mode that generates the minimum encoding error.

[00067] As the coding information about the coded depth and the coding mode can be assigned to a predetermined data unit out of a corresponding coding unit, a prediction unit, and a minimum unit, the coding information extractor and image data 220 can extract information about the

29/93 coded depth and coding mode according to predetermined data units. The predetermined data units to which the same information about the coded depth and the coding mode is assigned can be inferred to be the data unit included in the same maximum coding unit.

[00068] The image data decoder 230 restores the current frame by decoding the image data in each maximum coding unit based on the information on the coded depth and the coding mode according to the maximum coding units. In other words, the image data decoder 230 can decode the decoded image data based on the extracted information about the partition type, the prediction mode, and the transformation unit for each encoding unit among the encoding units that have the tree structure included in each maximum coding unit. A decoding process can include a prediction including intra-prediction and motion compensation, and a reverse transformation. The inverse transformation can be performed according to the inverse orthogonal transformation or inverse integer transformation method.

[00069] The image data decoder 230 can perform at least one of intra-prediction and motion compensation according to a partition and a prediction mode of each encoding unit, based on the information on the partition type and the prediction mode of the coding unit prediction unit according to the coded depths.

[00070] In addition, the image data decoder 230

30/93 can perform reverse transformation according to each transformation unit in the coding unit, based on information about the size of the transformation unit of the coding unit according to the coded depths, in order to perform the reverse transformation according to with the maximum coding units.

[00071] The image data decoder 230 can determine at least one coded depth of a current maximum coding unit using division information according to the depths. If the split information indicates that the image data is no longer divided at the current depth, the current depth is an encoded depth. Consequently, the image data decoder 230 can decode the encoded data of at least one coding unit corresponding to each coded depth in the current maximum coding unit using information about the partition type of the prediction unit, the prediction mode. , and the size of the processing unit for each coding unit corresponding to the coded depth, and outputting the image data from the current maximum coding unit.

[00072] For example, data units containing the encoding information including the same division information can be compiled by looking at the set of encoding information assigned to the predetermined data unit from within the encoding unit, the prediction unit, and the minimum unit, and the compiled data units can be considered to be a data unit to be decoded by the image data decoder 230 in the same encoding mode.

31/93 [00073] Video decoding equipment 200 can obtain information about at least one encoding unit that generates the minimum encoding error when encoding is performed recursively for each maximum encoding unit, and can use the information to decode the current image. In other words, coding units having the tree structure determined to be the optimal coding unit in each maximum coding unit can be decoded. In addition, the maximum size of the encoding unit is determined by considering the resolution and amount of image data.

[00074] Consequently, even if the image data has high resolution and a large amount of data, the image data can be efficiently decoded and restored using a size of an encoding unit and an encoding mode, which are determined adaptively according to the characteristics of the image data, using information about an optimal encoding mode received from an encoder.

[00075] A method of determining coding units having a tree structure, a prediction unit, and a transformation unit, according to an exemplary embodiment, will now be described with reference to Figures 3 to

13.

[00076] Figure 3 is a diagram to describe a concept of the coding units according to an exemplary modality. A size of a coding unit can be expressed in width x height, and can be 64x64, 32x32, 16x16 and 8x8. A 64x64 encoding unit can be divided into 64x64, 64x32, 32x64 or 32x32 partitions, and a

32/93 32x32 encoding can be divided into 32x32, 32x16, 16x32, or 16x16 partitions, a 16x16 encoding unit can be divided into 16x16, 16x8, 8x16 or 8x8 partitions, and an 8x8 encoding unit can be divided into 8x8, 8x4, 4x8 or 4x4 partitions.

[00077] With reference to fig. 3, exemplary first video data 310, with a resolution of 1920x1080, and an encoding unit with a maximum size of 64, and a maximum depth of 2. are exemplarily provided. In addition, second video data 320, with an 1920x1080 resolution, and an encoding unit with a maximum size of 64, and a maximum depth of 3. Third party video data 330, with a video data resolution 330, with a resolution of 352x288, is also exemplarily provided, and a coding unit with a maximum size of 16, and a maximum depth of 1. The maximum depth shown in Figure 3 denotes a total number of divisions from a maximum coding unit to a minimum decoding unit.

[00078] If the resolution is high or if the amount of data is large, the maximum size of a coding unit can be so large that not only increases the coding efficiency, but also accurately reflects the characteristics of a Image. Consequently, the maximum size of the encoding unit of the first and second video data 310 and 320 having the higher resolution than the third video data 330 can be 64.

[00079] Since the maximum depth of the first 310 video data is 2, the 315 encoding units of the first 310 video data may include an encoding unit

33/93 maximum having a long axis size of 64, and coding units having long axis sizes of 32 and 16 since depths are deepened to two layers by dividing the maximum coding unit twice. However, as the maximum depth of the third video data 330 is 1, encoding units 335 of the third video data 330 may include a maximum encoding unit having a long axis size of 16, and encoding units having a size long axis of 8 since depths are deepened to a layer by dividing once of the maximum coding unit.

[00080] Since the maximum depth of the second video data 320 is 3, the encoding units 325 of the second video data 320 may include a maximum encoding unit having a long axis size of 64, and encoding units having sizes 32, 16 and 8 long axis since depths are deepened to 3 layers by dividing the maximum coding unit three times. As the depth is deepened, detailed information can

be expressed accurately. [00081] A Figure 4 is one block diagram one encoder of image 400 based on units in coding, according with a modality exemplary. 0

image encoder 400 performs operations of the encoding unit determinator 120 of the video encoding apparatus 100 to encode the image data. That is, with reference to fig. 4, an intra-predictor 410 performs intraprediction in the coding units in an intra-mode, within a current frame 405, and a movement estimator 420 and a movement compensator 425 perform inter-estimation and

34/93 motion compensation in the coding units in an inter-mode between the current frame 405 using the current frame 405, and a reference frame 495.

[00082] Data emitted from intra-predictor 410, motion estimator 420, and motion compensator 425 are output as a quantized transformation coefficient through transformer 430 and a quantizer 440. The quantized transformation coefficient is restored as data in a spatial domain via a reverse quantizer 460 and a reverse transformer 470, and the data restored in the spatial domain is output as the frame of reference 495 after being post-processed through an unlocking unit 480 and a filtering unit loop 490. The quantized transformation coefficient can be output as a bit stream 455 through an entropy encoder 450.

[00083] For the image encoder 400 to be applied to the video encoding apparatus 100, all elements of the image encoder 400, that is, the intra-predictor 410, the motion estimator 420, the motion compensator 425, the transformer 430, the quantizer 440, the entropy encoder 450, the reverse quantizer 460, the reverse transformer 470, the unlocking unit 480, and the loop filtering unit 490 perform operations based on each coding unit among units of coding having a tree structure while considering the maximum depth of each maximum coding unit.

[00084] Specifically, the intra-predictor 410, the motion estimator 420, and the motion compensator 425 determine partitions and a prediction mode for each coding unit among the coding units having a structure of

35/93 tree while considering the maximum size and maximum depth of a current maximum coding unit, and transformer 430 determines the size of the transformation unit in each coding unit among the coding units having a tree structure.

[00085] Figure 5 is a block diagram of an image decoder 500 based on the coding units, according to an exemplary embodiment. With reference to fig. 5, an analyzer 510 analyzes the encoded image data to be decoded and encoding information required for decoding from a bit stream 505. The encoded image data is output as inverse quantized data via an entropy decoder 520 and an inverse quantizer 530, and inverse quantized data are restored to image data in a spatial domain through an inverse transformer 540.

[00086] An intra-predictor 550 performs intra-prediction in the coding units in an intra-mode with respect to the image data in the spatial domain, and a motion compensator 560 performs movement compensation in the coding units in an inter-mode. using a 585 frame of reference.

[00087] Image data in the spatial domain, which passed through intra-predictor 550 and motion compensator 560, can be output as a restored frame 595 after being post-processed through an unlocking unit 570 and a unit loop filtration 580. In addition, image data that is post-processed via the unlocking unit 570 and loop filtration unit 580 can be output as the frame of reference 585.

36/93 [00088] To decode the image data in the image data decoder 230 of the video decoding equipment 200, the image decoder 500 can perform operations that are carried out after the analyzer 510. In order for the image decoder 500 applied to the video decoding equipment 200, all the elements of the image decoder 500, that is, the analyzer 510, the entropy decoder 520, the inverse quantizer 530, the inverse transformer 540, the intra-predictor 550, the motion compensator 560, unlocking unit 570, and loop filtration unit 580 perform operations based on the coding units having a tree structure for each maximum coding unit.

[00089] Specifically, intra-predictor 550 and motion compensator 560 perform operations based on partitions and in a prediction mode for each of the coding units having a tree structure, and the reverse transformer 540 performs operations based on in one transformation unit size for each encoding unit.

[00090] Figure 6 is a diagram illustrating units of deeper coding according to depths, and partitions, according to an exemplary modality.

[00091] Video encoding apparatus 100 and video decoding equipment 200 use hierarchical encoding units in order to consider the characteristics of an image. A maximum height, a maximum width, and a maximum depth of the coding units can be determined adaptively according to the characteristics of the image, or they can be adjusted differently by a user. Coding unit sizes

37/93 depths, according to the depths, can be determined according to the predetermined maximum size of the coding unit.

[00092] With reference to Fig. 6, in a hierarchical structure 600 of the coding units, according to an exemplary modality, the maximum height and the maximum width of the coding units are individually 64, and the maximum depth is 4 As a depth is deepened along a vertical axis of the hierarchical structure 600, the height and width of the deepest coding unit are individually divided. In addition, a prediction unit and the partitions, which are the bases for prediction coding for each deeper coding unit, are shown along a horizontal axis of the hierarchical structure 600.

[00093] That is, a first coding unit 610 is a maximum coding unit in hierarchical structure 600, where a depth is 0 and a size, that is, a height by width, is 64x64. The depth is deepened along the vertical axis, and there is a second coding unit 620, having a size of 32x32, and a depth of 1; a third coding unit 630, having a size of 16x16, and a depth of 2; a fourth coding unit 640, having a size of 8x8, and a depth of 3; and a fifth coding unit 650, having a size of 4x4, and a depth of 4. The fifth coding unit 650 having a size of 4x4 and a depth of 4 is a minimum coding unit.

[00094] The prediction unit and partitions of a coding unit are arranged along the horizontal axis according to each depth. That is, if the first unit of

38/93 encoding 610, having the size of 64x64, and the depth of 0, is a prediction unit, the prediction unit can be divided into partitions included in the first encoding unit 610, that is, a partition 610 having a size 64x64, partitions 612 having the size of 64x32, partitions 614 having the size of 32x64, or partitions 616 having the size of 32x32.

[00095] Similarly, a prediction unit of the second coding unit 620 having the size of 32x32 and the depth of 1 can be divided into partitions included in the second coding unit 620, that is, a partition 620 having a size of 32x32, partitions 622 having a size of 32x16, partitions 624 having a size of 16x32, and partitions 626 having a size of 16x16.

[00096] Similarly, a prediction unit of the third encoding unit 630 having the size of 16x16 and the depth of 2 can be divided into partitions included in the third encoding unit 630, that is, a partition having a size of 16x16 included in the third encoding unit 630, partitions 632 having a size of 16x8, partitions 634 having a size of 8x16, and partitions 636 having a size of 8x8.

[00097] Similarly, a prediction unit of the fourth coding unit 640 having the size of 8x8 and the depth of 3 can be divided into partitions included in the fourth coding unit 640, that is, a partition having a size of 8x8 included in the fourth encoding unit 640, partitions 642 having a size of 8x4, partitions 644 having a size of 4x8, and partitions 646 having a size of

4x4.

39/93 [00098] The fifth coding unit 650 having the size of 4x4 and the depth of 4 is the minimum coding unit and a coding unit of the lowest depth. A prediction unit of the fifth coding unit 650 is designated only for a partition having a size of 4x4.

[00099] To determine at least one coded depth of the coding units constituting the maximum coding unit 610, the coding unit determinator 120 of the video coding apparatus 100 performs coding for the coding units corresponding to each depth included in the maximum coding unit 610.

[000100] A number of deeper coding units, according to depths including data in the same range and in the same size, increases as the depth is deepened. For example, four coding units corresponding to a depth of 2 are required to cover the data that is included in a coding unit corresponding to a depth of 1. Consequently, to compare the results of coding the same data according to the depths , the coding unit corresponding to the depth of 1; and four coding units corresponding to the depth of 2; are individually coded.

[000101] To perform the coding for a current depth between the depths, a minimum coding error can be selected for the current depth by performing coding for each prediction unit in the coding units corresponding to the current depth, along the horizontal axis of the hierarchical structure 600.

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Alternatively, the minimum coding error can be searched by comparing the minimum coding errors according to the depths, by performing coding for each depth as the depth is deepened along the vertical axis of the 600 hierarchical structure. a partition having the minimum coding error in the 610 coding unit can be selected as the coded depth and a partition type of the 610 coding unit.

[000102] Figure 7 is a diagram to describe a relationship between a coding unit 710 and transformation units 720, according to an exemplary embodiment.

[000103] The video encoding apparatus 100 or 200 encodes or decodes an image according to the encoding units having sizes less than or equal to a maximum encoding unit for each maximum encoding unit. Transformation unit sizes for transformation during coding can be selected based on data units that are no larger than a corresponding coding unit.

[000104] For example, in the video encoding or decoding equipment 100 or 200, if a size of the encoding unit 710 is 64x64, the transformation can be performed using the transformation units 720 having a size of 32x32.

[000105] In addition, the data of the encoding unit 710 having the size of 64x64 can be encoded by performing the transformation in each of the transformation units having the size of 32x32, 16x16, 8x8, and 4x4, which are smaller than 64x64, and then a transformation unit

41/93 having the minimum coding error can be selected.

[000106] Figure 8 is a diagram for describing coding information for coding units corresponding to a

depth coded, in wake up with one modality exemplary. With reference to Fig. 8 a unity of exit 130 of device in coding in video 100 can code and

transmitting information 800 about a partition type, information 810 about a prediction mode, and information 820 about a size of a transformation unit for each encoding unit corresponding to an encoded depth, such as information about an encoding mode.

[000107] Partition type information 800 is information about a partition format obtained by dividing a prediction unit from a current encoding unit, where the partition is a data unit for prediction encoding of the drive unit current encoding. For example, a current encoding unit CU_0 having a size of 2Nx2N can be divided into any one of an 802 partition having a size of 2Nx2N, an 804 partition having a size of 2NxN, an 806 partition having a size of Nx2N, and an 808 partition having an NxN size. Here, information 800 about a partition type is established to indicate one of partition 804 having a size of 2NxN, partition 806 having a size of Nx2N, and partition 808 having a size of NxN.

[000108] Information 810 on the prediction mode indicates a prediction mode for each partition. For example, information 810 may indicate a prediction encoding mode performed on a partition indicated by information 800, that is, an intra-mode 812, an inter-mode 814, or a hop mode 816.

42/93 [000109] Information 820 on the size of a transmission unit indicates a transformation unit to be based on when the transformation is performed in a current coding unit. For example, the transformation unit can be a first intra-transformation unit 822, a second intra-transformation unit 824, a first inter-transformation unit 826, or a second intra-transformation unit 828.

[000110] An image data and encoding information extractor 220 from a video decoding equipment 200 can extract and use information 800, 810 and 820 for decoding, according to each deeper encoding unit.

[000111] Figure 9 is a diagram of deeper coding units according to depths, according to an exemplary modality.

[000112] Division information can be used to indicate a change in depth. The split information indicates whether a coding unit of a current depth is divided into coding units of a lower depth.

[000113] Referring to Fig. 9, a prediction unit 910 for prediction encoding of an encoding unit 900 having a depth of 0 and a size of 2N_0x2N_0 can include partitions of a partition type 912 having a size of 2N_0x2N_O, a partition type 914 having a size of 2N_0xN_0, a partition type 916 having a size of N_0x2N_0, and a partition type 918 having a size of N_0xN_0. Although Figure 9 illustrates only the partition types 912 to 918 that are obtained by symmetrically dividing the

43/93 prediction unit 910, it is understood that a partition type is not limited to this. For example, according to another exemplary embodiment, the partitions of the prediction unit 910 may include asymmetric partitions, partitions having a predetermined shape and partitions having a geometric shape.

[000114] Prediction encoding is performed repeatedly on a partition having a size of 2N_0x2N_0, two partitions having a size of 2N_0xN_0, two partitions having a size of N_0x2N_0, and four partitions having a size of N_0xN_0, according to each partition type. Prediction coding in an intra-mode and an inter-mode can be performed on partitions having the sizes of 2N_0x2N_0, N_0x2N_0, 2N_0xN_0 and N_OxN_0. Prediction encoding in a jump mode is performed only on the partition having the size of 2N_0x2N_0.

[000115] Coding errors including prediction coding on partition types 912 to 918 are compared, and the minimum coding error is determined between partition types. If a coding error is less in one of partition types 912 to 916, the prediction unit 910 may not be broken down to a lower depth.

[000116] For example, if the encoding error is the smallest in partition type 918, a depth is changed from 0 to 1 to divide partition type 918 in operation 920, and encoding is performed repeatedly on encoding units 930 having a depth of 2 and a size of N_0xN_0 to look for a minimum coding error.

[000117] A prediction unit 940 for prediction encoding of the encoding unit 930 having a depth

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of 1 and one size of 2N_lx2N_l (= N_0xN_0) can include partitions in a type of partition 942 by having one size in 2N_lx2N_l , one partition type 944 by having one size in 2N_lxN_l, one partition type 946 by having one size in N_lx2N_l, and a kind of partition 948 by having one size in N_lxN_l. [000118] How An example, if one mistake coding is O smaller in type partition 948, one depth is changed from 1

to 2 to divide partition type 948 into operation 950, and encoding is performed repeatedly on encoding units 960, which have a depth of 2 and a size of N_2xN_2 to look for a minimal encoding error.

[000119] When a maximum depth is d, division operations according to each depth can be performed even when a depth becomes d-1, and the division information can be encoded even when a depth is one from 0 to d- 2. For example, when coding is performed even when the depth is d-1 after a coding unit corresponding to a depth of d-2 is divided in operation 970, a prediction unit 990 for prediction coding of a coding unit 980 having a depth of d-1 and a size of 2N_ (d-1) x2N_ (d-

1) can include partitions from one type in partition 992 by having one size of 2N_ (d-l) x2N_ (d-l), one type in partition 994 by having one size of 2N_ (d-l) xN_ (d-l), one type in partition 996 by having one size of N_ (d-1) x2N_ (d-1), one type in partition 998 by having one

size of N_ (d-1) xN_ (d-1).

[000120] Prediction encoding can be performed repeatedly on a partition having a size of 2N_ (d

45/93

l) x2N_ (dl), two partitions having a size of 2N_ (d-1) xN_ (d1), two partitions having a size of N_ (d-1) x2N_ (d-1), four partitions having a size of N_ (d-1) xN_ (d-1) among partition types 992 to 998 to search for a partition type having a minimal coding error.

[000121] Even when partition type 998 has the minimum coding error, as a maximum depth is d, a CU_ coding unit (dl), having a depth of d-1 is no longer divided to a lower depth, and a coded depth for the coding units constituting a current maximum coding unit 900 is determined to be d-1 and a partition type of the current maximum coding unit 900 can be determined to be N_ (d-1) xN_ (d- 1) . In addition, since the maximum depth is d and a minimum coding unit 980 having the lowest depth of d-1 is no longer divided to a lower depth, the division information for the minimum coding unit 980 is not established.

[000122] The data unit 999 can be a minimum unit for the current maximum encoding unit. A minimum unit according to an exemplary modality can be a rectangular data unit obtained by dividing a minimum coding unit 980 by 4. By performing the coding repeatedly, the video coding apparatus 100 can select a depth having the error of minimum coding by comparing coding errors according to the depths of the coding unit 900 to determine a coded depth, and to establish a corresponding partition type and prediction mode as a depth coding mode

46/93 coded.

[000123] As such, the minimum coding errors according to depths are compared across all depths

from 1 to d, and The depth by having the smallest mistake in coding Can be determined how an depth coded. THE depth coded, the type partition gives unity in prediction, and the prediction mode i can be coded and

transmitted as information about an encoding mode. In addition, since a coding unit is divided from a depth of 0 to a coded depth, only the coded depth division information is set to 0, and the depth division information excluding the coded depth is set to 1 .

[000124] The encoding information and image data extractor 220 of the video decoding equipment 200 can extract and use the information about the encoded depth and the prediction unit of the encoding unit 900 to decode partition 912. The decoding equipment video decoding 200 can determine a depth, in which the split information is 0, as an encoded depth using the split information according to the depths, and use the information about a corresponding depth encoding mode for decoding.

[000125] Figures 10 to 12 are diagrams to describe a relationship between coding units 1010, prediction units 1060, and transformation units 1070, according to an exemplary embodiment.

[000126] With reference to Fig. 10, the coding units 1010 are coding units that have a structure of

47/93 tree, corresponding to the coded depths determined by the video coding apparatus 100, in a maximum coding unit. With reference to Figures 11 and 12, the prediction units 1060 are partitions of the prediction units of each of the coding units 1010, and the transformation units 1070 are transformation units of each of the coding units 1010.

[000127] When a maximum coding unit depth is 0 in coding units 1010, the depths of coding units 1012 and 1054 are 1, the depths of coding units 1014, 1016, 1018, 1028, 1050, and 1052 are 2, the depths of the decoding units 1020, 1022, 1024, 1026, 1030, 1032 and 1048 are 3, and the depths of the encoding units 1040, 1042, 1044 and 1046 are 4.

[000128] In the prediction units 1060, some coding units 1014, 1016, 1022, 1032, 1048, 1050, 1052, 1054 are obtained by dividing the coding units into the 1010 coding units. In other words, partition types in the coding units 1014, 1022, 1050, and 1054 have a size of 2NxN, the partition types in the coding units 1016, 1048 and 1052 have a size of Nx2N, and a partition type of the coding unit 1032 has a size of NxN. The prediction units and partitions of the 1010 coding units are less than or equal to each coding unit.

[000129] Transformation or inverse transformation is performed on the image data of the 1052 encoding unit in the 1070 transformation units in a data unit that is smaller than the 1052 encoding unit.

48/93 coding units 1014, 1016, 1022, 1032, 1048, 1050 and 1052 in transformation units 1070 are different from those in prediction units 1060 in terms of sizes and shapes. In other words, the video encoding and decoding equipment 100 and 200 can perform intraprediction, motion estimation, motion compensation, transformation, and reverse transformation individually in a data unit in the same encoding unit.

[000130] Consequently, coding is performed recursively in each of the coding units having a hierarchical structure in each region of a maximum coding unit to determine an optimal coding unit, and thus coding units that have a structure of recursive tree can be obtained. The encoding information can include division information about a coding unit, information about a partition type, information about a prediction mode, and information about a size of a transformation unit. Table 1 shows the encoding information that can be established by the video encoding and decoding equipment 100 and 200.

49/93

Table 1

Divided information 0 (Coding in the Coding Unit having a size of 2Nx2N and Current Depth of d) Split information 1 Way of Prediction Partition Type Transformation Unit Size Repeatedly Encode Coding Units having a Depth Less Than d + 1 Salto Intra / lnter (Only 2Nx2N) Kind of Partition Symmetrical Kind of Partition Asymmetric 0 Transformation Unit split information Divided information 1 of Unity of T ransformation 2Nx2N2NxN Nx2NNxN 2NxnU2NxnDn Lx2NnRx2N 2Nx2N NxN (Type Symmetrical) N / 2xN / 2 (Type Asymmetric)

[000131] Output unit 130 of video encoding apparatus 100 can output encoding information about encoding units having a tree structure, and the encoding information and image data extractor 220 of the video decoding equipment 200 can extract the encoding information about the encoding units having a tree structure from a received bit stream.

[000132] The split information indicates whether a current coding unit is divided into coding units of a lower depth. If the division information for a current depth d is 0, a depth, in which a current coding unit is no longer divided into a lower depth, is a coded depth, and so information about a partition type, the mode of prediction, and a size of a transformation unit, can be defined for the coded depth. If the current coding unit is further divided according to the division information, coding is carried out independently into four coding units divided by a depth

50/93 lower.

[000133] A prediction mode can be one of: an intra-mode, an inter-mode, and a jump mode. The intra-mode and the inter-mode can be set on all partition types, and the jump mode is set only on a partition type having a size of 2Nx2N.

[000134] Partition type information can indicate symmetric partition types having sizes of 2Nx2N, 2NxN, Nx2N, and NxN, which are obtained by symmetrically dividing a height or width of a prediction unit, and asymmetric partition types having sizes of 2NxnU, 2NxnD, nLx2N and nRx2N, which are obtained by asymmetrically dividing the height or width of the prediction unit. The types of asymmetric partition having the sizes of 2NxnU and 2NxnD can be obtained respectively by dividing the height of the prediction unit in 1: 3 and 3: 1, and the types of asymmetric partition having the sizes of nLx2N and nRx2N can be obtained respectively by dividing the width of the prediction unit into 1: 3 and 3: 1.

[000135] The size of the processing unit can be adjusted to be of two types in the intra-mode and two types in the inter-mode. For example, if the transformation unit split information is 0, the size of the transformation unit can be 2Nx2N, which is the size of the current coding unit. If transformation unit division information is 1, the transformation units can be obtained by dividing the current coding unit. In addition, if a division type of the current coding unit having the size of 2Nx2N is an asymmetric partition type, a size of a transformation unit can be NxN, and if

51/93 the partition type of the current coding unit is an asymmetric partition type, the size of the transformation unit can be N / 2xN / 2.

[000136] The coding information about the coding units having a tree structure can include at least one of a coding unit corresponding to a coded depth, a prediction unit, and a minimum unit. The coding unit corresponding to the coded depth can include at least one of a prediction unit and a minimum unit containing the same coding information.

[000137] Consequently it is determined whether the adjacent data units are included in the same coding unit corresponding to the coded depth by comparing the coding information of the adjacent data units. In addition, a corresponding coding unit corresponding to a coded depth is determined using the coding information from a data unit, and thus a distribution of the coded depths in a maximum coding unit can be determined.

[000138] Consequently, if a current coding unit is predicted based on the coding information of the adjacent data units, coding information of the data units in deeper coding units adjacent to the current coding unit can be directly queried and used . However, it is understood that another exemplary modality is not limited to this. For example, according to another exemplary embodiment, if a current encoding unit is provided based on the encoding information from the adjacent data unit, the data units adjacent to the

52/93 current encoding are searched using information encoded from the data units, and the adjacent encoded units searched can be referred to to predict the current encoding unit.

[000139] Figure 13 is a diagram to describe a relationship between a coding unit, a prediction unit or a partition, and a transformation unit, according to the exemplary coding mode information in Table 1, according to with an exemplary modality.

[000140] With reference to Figure 13, a maximum coding unit 1300 includes coding units 1302 1304, 1306, 1312, 1314, 1316 and 1318 of coded depths. Here, as the coding unit 1318 is a coding unit of a coded depth, the divided information can be set to 0. Information about a partition type of the coding unit 1318 having a size of 2Nx2N can be set to be a of: a partition type 1322 having a size of 2Nx2N, a partition type 1324 having a size of 2NxN, a partition type 1326 having a size of Nx2N, a partition type 328 having a size of NxN, a type of partition 1332 having a size of 2NxnU, a partition type 1334 having a size of 2NxnD, a partition type 1336 having a size of nLx2N, and a partition type 1338 having a size of nRx2N.

[000141] When the partition type is set to be symmetric, that is, the partition type 1322, 1324, 1326 or 1328, a 1342 transformation unit having a size of 2Nx2N is established if split information (TU size flag) of a transformation unit is 0, and a transformation unit 1344 having an NxN size is established

53/93 if a TU size flag is 1.

[000142] When the partition type is established to be asymmetric, that is, partition type 1332, 1334, 1336 or 1338, a 1352 transformation unit having a size of 2Nx2N is established if a TU size flag is 0, and a transformation unit 1354 having a size of N / 2xN / 2 is established if a flag of size TU is 1.

[000143] With reference to Figure 13, the TU size flag is a flag having a value of 0 or 1, however the TU size flag is not limited to 1 bit, and the transformation unit can be divided hierarchically having a tree structure while the TU size flag increases from 0.

[000144] In this case, the size of a transformation unit that was effectively used can be expressed using a TU size flag of a transformation unit, according to an exemplary modality, together with a maximum size and a size minimum of the processing unit. According to an exemplary embodiment, the video encoding apparatus 100 is capable of encoding maximum transformation unit size information, minimum transformation unit size information, and a maximum TU size flag. The result of encoding the maximum transformation unit size information, minimum transformation unit size information, and the maximum TU size flag can be inserted into an SPS. According to an exemplary embodiment, the video encoding equipment 200 can decode video using the maximum transformation unit size information, the minimum transformation unit size information, and

54/93 of the maximum TU size flag.

[000145] For example, if the size of a current encoding unit is 64x64 and a maximum transformation unit size is 32x32, then the size of a transformation unit can be 32x32 when a TU size flag is 0, it can be 16x16 when the TU size flag is 1, and can be 8x8 when the TU size flag is 2.

[000146] As another example, if the current encoding unit size is 32x32 and a minimum transformation unit size is 32x32, then the transformation unit size can be 32x32 when the TU size flag is 0. Here, the TU size flag cannot be set to a value other than 0, as the size of the transformation unit cannot be less than 32x32.

[000147] As another example, if the current encoding unit size is 64x64 and a maximum TU size flag is 1, then the TU size flag can be 0 or 1. Here, the TU size flag cannot be adjusted to a value other than 0 or 1.

[000148] Thus, if the maximum TU size flag is set to MaxTransformSizelndex, a minimum transformation unit size is MinTransformSize, and a transformation unit size is RootTuSize when the TU size flag is 0, a unit size Current minimum transformation currMinTuSize that can be determined in a current coding unit, can be defined by Equation (1):

CurrMinTuSize = max (MinTransformSize, RootTuSize / (2 ^yx MaxTransformS izelndex)) ... (1)

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[000149] In comparison with the size of unity in current minimum transformation CurrMinTuSize what can to be determined in the unit current encoding, one size in unity transformation RootTuSize when the flare gun in size TU is 0, can denote a size in unity in maximum transformation that can be selected at the system. At Equation (1), RootTuSize (2 ^A MaxTransformSizeIndex) denotes one size of unit of transformation when O size in unity transformation RootTuSize, when the flare gun in size TU is 0, the number of times is divided corresponding

the maximum TU size flag, and e MintransformSize denotes a minimum transformation size. Thus, a smaller value between RootTuSize / (2 ^A MaxTransformSizeIndex) and MinTransformSize can be the current minimum CurrMinTuSize transformation unit size that can be determined in the current coding unit.

[000150] According to an exemplary modality, the size of the maximum RootTuSize transformation unit may vary according to the type of prediction mode.

[000151] For example, if a current prediction mode is an inter-mode, then RootTuSize can be determined using Equation (2) below. In Equation (2), MaxTransformSize denotes a maximum transformation unit size, and PUSize denotes a current prediction unit size.

RootTuSize = min (MaxTransformSize, PUSize) .... (2) [000152] That is, if the current prediction mode is inter-mode, the RootTuSize transformation unit size when the TU size flag is 0, can be a smaller value between the maximum processing unit size and the size of

56/93 current prediction unit.

[000153] If a prediction mode for a current partition drive is an intra-mode, RootTuSize can be determined using Equation (3) below. In Equation (3), Partitionsize denotes the size of the current partition unit.

RootTuSize = min (MaxTransformSize, PartitionSize) ...... (3) [000154] That is, if the current prediction mode is intra-mode, the RootTuSize transformation unit size when the TU size flag is 0 it can be a smaller value between the maximum transformation unit size and the current partition unit size.

[000155] However, the current maximum RootTuSize transformation unit size that varies according to the type of a prediction mode in a partition unit is just an example and is not limited to that in another exemplary mode.

[000156] Figure 14 is a flow chart illustrating a method of encoding a video, according to an exemplary modality. With reference to Figure 14, in operation 1210, a current frame is divided into at least one maximum coding unit. A maximum depth indicating the total number of possible split times can be predetermined.

[000157] In operation 1220, a coded depth to produce a final coding result according to at least one divided region, which is obtained by dividing a region of each maximum coding unit according to the depths, is determined by coding at least one divided region, and a coding unit according to a tree structure is determined.

[000158] The maximum coding unit is divided

57/93 spatially whenever the depth is deepened, and thus it is divided into coding units of a lower depth. Each coding unit can be divided into coding units of another lower depth because it is spatially divided independently from adjacent coding units. Coding is performed repeatedly on each coding unit according to the depths.

[000159] In addition, a transformation unit according to the partition types having the minimum coding error is determined for each deepest coding unit. To determine a coded depth having a minimum coding error in each maximum coding unit, coding errors can be measured and compared across all the deepest coding units according to the depths.

[000160] In operation 1230, encoded image data constituting the final encoding result according to the encoded depth are output for each maximum encoding unit, with encoding information about the encoded depth and an encoding mode. Information about the encoding mode can include information about an encoded depth or divided information, information about a partition type of a prediction unit, a prediction mode, and a size of a transformation unit. The encoded information about the encoding mode can be transmitted to a decoder with the encoded image data.

[000161] Figure 15 is a flow chart illustrating a method of decoding a video, according to an exemplary modality.

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Referring to Figure 15, in operation 1310, a bit stream from an encoded video is received and analyzed.

[000162] In operation 1320, the encoded image data of a current frame assigned to a maximum encoding unit, and information about an encoded depth and an encoding mode according to the maximum encoding units are extracted from the flow of analyzed bits. The coded depth of each maximum coding unit is a depth that has the minimum coding error in each maximum coding unit. In the coding of each maximum coding unit, the image data is coded based on at least one data unit obtained by dividing the maximum coding unit hierarchically according to the depths.

[000163] According to the information about the coded depth and the coding mode, the maximum coding unit can be divided into coding units having a tree structure. Each of the coding units having the tree structure is determined as a coding unit corresponding to an encoded depth, and is optimally coded in order to produce the minimum coding error. Consequently, the coding and decoding efficiency of an image can be improved by decoding each fraction of encoded image data in the coding units after determining at least one coded depth according to the coding units.

[000164] In operation 1330, the image data of each maximum coding unit is decoded based on information about the coded depth and the coding mode of

59/93 according to the maximum coding units. The decoded image data can be reproduced by a reproduction device, stored in a storage medium, or transmitted over a network.

[000165] Next, the video encoding and decoding performed in an encoding tool operating mode considering a size of an encoding unit according to exemplary modalities, will be described with reference to Figures 16 to 23.

[000166] Figure 26 is a block diagram of a video encoding device 1400 based on an encoding tool considering the size of an encoding unit, according to an exemplary modality. Referring to Figure 16, apparatus 1400 includes a maximum coding unit divider 1410, a coding unit determiner 1420, and an output unit 1430.

[000167] 0 divisor of maximum coding unit 1410 divide one current image in at least one coding unit maximum. [000168] 0 determiner of unit 1420 encoding encode The at least an unity of maximum coding in units in coding corresponding to the depths. In that If determiner in unity of 1420 encoding can

encode a plurality of regions divided from at least one maximum coding unit in operating modes corresponding to the coding tools according to the depths of the coding units, respectively, based on a relationship between a depth of a coding unit, a encoding tool, and an operating mode.

60/93 [000169] The coding unit determiner 1420 encodes the coding units corresponding to all depths, compares the coding results with each other, and determines a depth of a coding unit having the highest coding efficiency as a coded depth. As in the divided regions of the at least one maximum coding unit, a depth having a higher coding efficiency may differ according to a location, a coded depth of each of the divided regions of the at least one maximum coding unit can be determined. regardless of those in other regions. Thus, more than one coded depth can be defined in a maximum coding unit.

[000170] Examples of a coding tool for coding may include quantization, transformation, intraprediction, inter-prediction, motion compensation, entropy coding and loop filtering, which are video coding techniques. According to an exemplary embodiment, in the video encoding apparatus 1400, each of the various encoding tools can be performed according to at least one mode of operation. Here, the term, mode of operation, indicates a way in which a coding tool is performed.

[000171] For example, if a coding tool is inter-prediction, a mode of operation of the coding tool can be classified into a first mode of operation in which an average value of the motion vectors of neighboring prediction units is selected, a second mode of operation in which a motion vector of a unit of

61/93 prediction at a specific location between neighboring prediction units is selected, and a third mode of operation in which a motion vector of a prediction unit that includes a template more similar to a template of a current prediction unit between units neighboring prediction variables is selected.

[000172] In accordance with an exemplary embodiment, the video encoding apparatus 1400 can variablely establish a mode of operation of an encoding tool according to the size of an encoding unit. In the present exemplary embodiment, the video encoding apparatus 1400 can variably establish a mode of operation of at least one encoding tool according to the size of an encoding unit. Since a depth of a coding unit corresponds to the size of the coding unit, the mode of operation of at least one coding tool can be determined based on the depth of the coding unit corresponding to the size of the coding unit. Thus, the relationship between the depth of a coding unit, a coding tool, and an operating mode can be established. Similarly, if a coding tool can be performed on a prediction unit or a partition of a coding unit, a mode of operation of the coding tool can be determined based on the size of a prediction unit or partition.

[000173] The video encoding device 1400 can establish the relationship between a depth of an encoding unit, an encoding tool, and an operating mode before encoding is carried out. For example,

62/93 according to another exemplary embodiment, the video encoding apparatus 1400 can establish the relationship between a depth of an encoding unit, an encoding tool and an operating mode by encoding the encoding units of at least one encoding unit. maximum coding corresponding to the depths in all operating modes of a predetermined coding tool and detecting an operating mode having the highest coding efficiency among the operating modes.

[000174] The video encoding apparatus 1400 can assign an operating mode causing extra code bits for encoding units corresponding to the depths, the sizes of which are equal to or greater than a predetermined size, and can assign an operating mode which does not cause extra code bits for the other encoding units, whose sizes are smaller than the predetermined size.

[000175] The video encoding apparatus 1400 can encode and transmit information regarding the relationship between a depth of an encoding unit, an encoding tool, and a mode of operation in slice units, frame units, image units, or GOP units of an image. According to another exemplary modality, the video encoding device 1400 can insert information related to encoding and information regarding the relationship between a depth of an encoding unit, a coding tool, and an operation mode in an SPS.

[000176] If the coding unit determiner 1420 performs intra-prediction, which is a type of a coding tool, an intra-prediction mode of operation can be

63/93 classified according to a number of prediction directions, that is, directions in which neighborhood information can be used as a reference. Thus, an intraprediction mode of operation performed by the video encoding apparatus 1400 may include intraprediction modes representing the number of prediction directions that vary according to the size of an encoding unit.

[000177] In addition, if the 1420 coding unit determiner performs intra-prediction, an intra-prediction mode of operation can be classified according to whether smoothing is being performed in consideration of an image pattern. Thus, an intra-prediction mode of operation performed by the video encoding device 1400 can represent whether intra-prediction should be performed according to the size of an encoding unit by differentiating an intra-prediction mode for smoothing a region of a coding unit and an intra-prediction mode to maintain a borderline between them.

[000178] If the coding unit determinator 1420 performs inter-prediction, which is another type of coding tool, the coding unit determinator 1420 can selectively perform at least one method of determining a motion vector. Thus, an interpretation mode performed by the video encoding apparatus 1400 may include an inter-prediction mode representing a method of determining a motion vector, which is performed selectively according to the size of an encoding unit.

[000179] If the encoding unit determiner 1420 performs transformation, which is another type of

64/93 encoding, a 1420 encoding unit determiner can selectively perform rotational transformation according to the pattern of an image. The coding unit determinant 1420 can store a rotational transformation matrix to be multiplied by a data matrix of predetermined size, which is a transformation target, in order to effectively perform the rotational transformation. Thus, a transformation mode of operation performed by the video encoding apparatus 1400 may include a transformation mode representing an index of a rotational transformation matrix corresponding to the size of an encoding unit.

[000180] If the coding unit determiner 1420 performs quantization, which is another type of coding tool, then a delta quantization parameter representing the difference between a current quantization parameter and a representative predetermined quantization parameter can be used. Thus, a quantization mode of operation performed by the video encoding apparatus 1400 may include a quantization mode indicating whether the delta quantization parameter that varies according to the size of an encoding unit should be used.

[000181] If the encoding unit determiner 1420 performs interpellation, which is another type of encoding tool, the interpellation filter can be used. The coding unit determinator 1420 can selectively establish the coefficients or number of leads of the interpolation filter based on the size of a coding unit, a prediction unit or partition and the depth of a coding unit. So, a way of

65/93 interpolation filtering operation performed by the 1400 video encoding apparatus may include an interpolation mode indicating coefficients or the number of derivations of an interpolation filter that varies according to the size or depth of an encoding unit and the size of a prediction unit or partition.

[000182] The output unit 1430 can produce a bit stream, in which encoded video data (i.e., an end result of the encoding received from the encoding unit determiner 1420), information with respect to an encoded depth, and an encoding mode are included for each of at least one maximum encoding unit. The encoded video data can be a set of a plurality of fragments of video data that are encoded in encoding units corresponding to the encoded depths of the divided regions of the at least one maximum encoding unit, respectively.

[000183] In addition, the modes of operation of the coding units mentioned above, for coding units corresponding to depths, can be encoded in the form of information regarding the relationship between a depth of a coding unit, a coding tool, and an operating mode and then be inserted into a bit stream.

[000184] According to an exemplary embodiment, the video encoding apparatus 1400 can perform an encoding tool, such as quantization, transformation, intraprediction, inter-prediction, motion compensation, entropy coding and loop filtration. These coding tools can be performed in different modes of

66/93 operation in coding units corresponding to the depths, respectively. The above modes of operation are just illustrative examples provided for convenience of explanation, and the relationship between a depth of a coding unit (or the size of a coding unit), a coding tool, and a mode of operation on the instrument. video encoding 1400 is not limited to the above exemplary modalities.

[000185] Figure 17 is a block diagram of a video decoding device 1500 based on an encoding tool considering an encoding unit size, according to an exemplary embodiment. Referring to Figure 17, the video decoding apparatus 1500 includes a receiver 1510, an extractor 1520, and a decoder 1330.

[000186] The receiver 1510 receives and analyzes a bit stream including encoded video data. The 1520 extractor extracts the encoded video data, information regarding encoding, and information regarding the relationship between a depth of an encoding unit, an encoding tool, and an operating mode from the bit stream received via the receiver 1510.

[000187] The encoded video data is obtained by encoding image data in maximum encoding units. The image data in each of the maximum coding units are divided hierarchically into a plurality of regions divided according to depths, and each of the divided regions is coded in a coding unit of a corresponding coded depth. Coding information includes

67/93 information regarding the coded depths of the maximum coding units and a coding mode.

[000188] For example, information regarding the relationship between a depth of a coding unit, a coding tool, and a mode of operation can be established in units of image data, for example, maximum coding units, units of image frame, field units, slice units, or GOP units. In another example, information regarding coding, and information regarding the relationship between a depth of a coding unit, a coding tool and a mode of operation can be extracted from an SPS. Image data encoded in image data encoding units can be decoded in a selective operating mode of an encoding tool, based on information related to the relationship between a depth of an encoding unit, an encoding tool, and an operation mode, which is defined in predetermined units of image data.

[000189] The decoder 1530 can decode the encoded video data in maximum encoding units and in modes of operation of the encoding tools in encoding units corresponding to at least one encoded depth, respectively, based on the encoding information and the information regarding the relationship between a depth of a coding unit, a coding tool and an operating mode that are extracted by the extractor 1520. The operating mode of a coding tool can be established according to a size of a coding unit coding. As a unit size of

68/93 coding corresponding to the coded depth corresponds to the coded depth, the mode of operation of the coding tool for the coding unit corresponding to the coded depth can be determined based on the coded depth. Similarly, if the coding tool for the coding unit is performed on the basis of a prediction unit or a partition of the coding unit, the mode of operation of the coding tool can be determined based on the size of a prediction unit or of a partition.

[000190] Even if the relationship between a depth of an encoding unit, an encoding tool, and an operating mode is established for an encoding tool, the decoder 1530 can perform a decoding tool corresponding to the encoding tool. For example, the decoder 1530 can inversely quantize a bit stream in a coding unit corresponding to a coded depth, based on information regarding a relationship between a coding unit depth, quantization, and an operating mode.

[000191] If the decoder 1530 performs intra prediction, which is a type of a decoding tool, the decoder 1530 can perform intra prediction in a current coding unit corresponding to a coded depth, based on information regarding the relationship between a depth of a coding unit, intraprediction, and an intraprediction mode. For example, the 1530 decoder can perform intra-prediction in the current coding unit corresponding to the coded depth based on information regarding the relationship between a depth

69/93 of a coding unit, intra-prediction, and an intra-prediction mode, and neighborhood information according to a number of intra-prediction directions corresponding to the size of the current coding unit.

[000192] Furthermore, the decoder 1530 can determine whether it performs intra-prediction according to the coded unit of the current coding unit by means of intraprediction differentiation to smooth an intraprediction mode to maintain a borderline between them, based on in the information regarding the relationship between a depth of a coding unit, intra-prediction, and an intra-prediction mode.

[000193] If the decoder 1530 performs inter-prediction, which is another type of decoding tool, the decoder 1530 can perform inter-prediction in the current coding unit corresponding to the coded depth based on the information regarding the relationship between a depth of a coding unit, inter-prediction, and an interpredition mode. For example, the decoder 1530 can perform the mode of inter-prediction in the current coding unit of the coded depth using a method of determining a motion vector, based on information regarding the relationship between a depth of a coding unit, inter-prediction and the mode of inter-prediction.

[000194] If the decoder 1530 performs reverse transformation, which is another type of decoding tool, the decoder 1530 can selectively perform reverse rotational transformation based on information regarding the relationship between a depth of a coding unit, transformation, and a transformation mode. Thus, the 1530 decoder can perform rotational transformation

70/93 inverse in the current coding unit corresponding to the coded depth using a rotational transformation matrix of an index corresponding to the coded depth, based on information regarding the relationship between a depth of a coding unit, transformation, and mode of reverse transformation.

[000195] If the decoder 1530 performs reverse quantization, which is another type of encoding tool, the decoder 1530 can perform reverse quantization in the current encoding unit corresponding to the encoded depth using a delta quantization parameter corresponding to the encoded depth, based on information regarding a depth of a coding unit, quantization and a quantization mode.

[000196] If the 1530 decoder performs interpellation or extrapolation, which is another type of encoding tool, a filter for interpellation or extrapolation can be used. The decoder 1530 can perform filtration using the filter for interpolation or extrapolation to a current coding unit corresponding to the coded depth, using coefficients or the number of filter leads for interpolation or extrapolation based on the filtration operation mode for interpolation or extrapolation. The filtering operation mode for interpolation or extrapolation may correspond to at least one of the current coding unit size, and the size of a current prediction unit or partition of the current coding unit.

[000197] The video decoding device 1500 can reconstruct the original image from the image data decoded by the decoder 1530. The reconstructed image

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can be reproduced by a display device ( no shown) or can be stored in a storage medium (not shown). [000198] No Device of coding of video 1400 and at the Device of decoding of video 1500's wake up with modalities copies, ( 9 size of a unity in coding may vary from a deal with the CARACTERISTICS in An image and a coding efficiency of Image. 0 size of a unit of data, such as a unity in coding, one unit of prediction, or a unity in

transformation, can be enlarged to encode a large amount of image data, for example, a high resolution or high quality image. The size of a macroblock having a hierarchical structure according to the H.264 standards can be 4x4, 8x8 or 16x16, but the video encoding device 1400 and the video decoding device 1500 according to one or more exemplary modalities you can expand the size of a data unit to 4x4, 8x8, 16x16, 32x32, 64x64, 128x128 or more.

[000199] The larger the data unit, the more image data is included in the data unit, and the more diverse image characteristics in the data units. Thus, it would be inefficient to encode all data units having various sizes using only one encoding tool. [000200] Consequently, the video encoding apparatus 1400 can determine a depth of an encoding unit and an operating mode of an encoding tool according to the characteristics of the image data in order to increase the encoding and encoding efficiency information regarding a relationship between the

72/93 depth of the encoding unit, the encoding tool, and the operating mode. In addition, the video decoding apparatus 1500 can reconstruct the original image by decoding a received bit stream, based on information regarding a relationship between the depth of the encoding unit, the encoding tool and the mode of operation.

[000201] Consequently, the video encoding apparatus 1400 and the video decoding apparatus 1500 can effectively encode and decode a large amount of image data, such as a high resolution or high quality image, respectively.

[000202] Figure 18 is a diagram to describe a relationship between the size of a coding unit, a coding tool, and an operating mode, according to an exemplary modality.

[000203] With respect to Figure 18, according to an exemplary modality, in a video encoding device 1400 or in a video decoding device 1500, a 4x4 encoding unit 1610, an encoding unit 8x8 1620, a unit 16x16 1630 encoding, a 32x32 1640 encoding unit, and 64x64 1650 encoding unit can be used as encoding units. If a maximum coding unit is the 64x64 1650 coding unit, a 64x64 1650 coding unit depth is 0, a 32x32 1640 coding unit depth is 1, a 16x16 163 coding unit depth is 2, a depth of 8x8 1620 coding unit is 3, and a 4x4 1610 coding unit depth is 4.

[000204] The video encoding device 1400 can

73/93 adaptively determine a mode of operation of a coding tool according to a depth of a coding unit. For example, if a first TOOL 1 encoding tool can be performed in a first TOOL 1-1 1660 operating mode, a second TOOL 1-2 1662 operating mode, and a third TOOL 1-3 operating mode, the device video encoder 1400 can perform the first TOOL 1 encoding tool in the first TOOL 1-1 1660 operating mode with respect to the 4x4 1610 encoding unit and 8x8 1620 encoding unit, perform the first TOOL 1 encoding tool in the second mode of operation 1662 with respect to the 16x16 1630 encoding unit and the 32x32 1640 encoding unit, and perform the first TOOL 1 encoding tool in the third 1664 operating mode with respect to the 16x64 encoding unit.

[000205] The relationship between the size of a coding unit, a coding tool and an operating mode can be determined by coding a current coding unit in all operating modes of a corresponding coding tool and detecting a mode of operation causing a coding result with a higher coding efficiency between operating modes, when coding the current coding unit. In another exemplary embodiment, the relationship between the size of a coding unit, a coding tool, and a mode of operation can be predetermined, for example, by at least one of the performance of a coding system, user requirements, or ambient conditions.

[000206] As the size of a maximum encoding unit is

74/93 fixed with respect to predetermined data, the size of a coding unit corresponds to a depth of the coding unit itself. Thus, a relationship between a coding tool adaptive to the size of a coding unit and a mode of operation can be encoded using information relating to a relationship between a depth of a coding unit, a coding tool, and a mode of operation.

[000207] Information regarding the relationship between a depth of a coding unit, a coding tool, and an operating mode can indicate optimal modes of operation of coding tools in units of depth of coding units, respectively.

Table 2

Unit depth encoding = 4 Unit depth encoding = 3 Unit depth encoding = 2 Unit depth encoding = 1 Unit depth encoding = 0 Way of operation of the 1 * tool coding first mode of operation first mode of operation second mode of operation second mode of operation third mode of operation Operating mode of ^the 2 encoding tool first mode of operation second mode of operation second mode of operation third mode of operation third mode of operation

[000208] According to Table 2, exemplary, the modes of operation of the first and the second coding tool can be used in a variable way to the coding units having depths 4, 3, 2, 1 and 0, respectively. Information regarding the relationship between a depth of a coding unit, a coding tool, and an operating mode can be encoded and

75/93 transmitted in sequence units, GOP units, image units, frame units, or slice units of an image.

[000209] Several exemplary modalities of a relationship between a depth of a coding unit, a coding tool, and an operating mode will now be described in detail.

[000210] Figure 19 is a diagram to describe a relationship between a depth of a coding unit, a coding tool (for example, inter-prediction), and a mode of operation, according to an exemplary modality.

[000211] If a video encoding device 1400 according to an exemplary modality performs inter-prediction, at least one method of determining a motion vector can be used. Thus, the inter-prediction mode of operation, which is a type of coding tool, can be classified according to a method of determining a motion vector.

[000212] For example, with reference to Figure 19, in a first inter-prediction operation mode, an average value of motion vectors mvpA, mvpB and mvpC of neighboring coding units A, B and C 1710, 1720 and 1730 is selected as an MVP predicted motion vector from a current 1700 coding unit, as indicated in Equation (4) below:

MVP = average (mvpA, mvpB, mvpC) ... (4).

[000213] If the first mode of operation is used, a calculation amount is low and extra code bits may not be used. Thus, even if inter-prediction is performed on small size coding units in the first

76/93 operation, an amount of calculation or an amount of bits to be transmitted is small.

[000214] For example, in a second interpretation mode of operation, an index of the motion vector of a coding unit that is selected as a predicted motion vector of the current coding unit 1700 among the motion vectors of the coding units neighboring A, B and C 1710, 1720 'and 1730, is displayed directly.

[000215] For example, if the video encoding device 1400 performs inter-prediction on the current encoding unit 1700, the mvpA motion vector of neighboring encoding unit A 1710 can be selected as an optimal predicted motion vector of the video encoding unit. current encoding 1700 and an index of the mvpA motion vector can be encoded. Thus, although extra code occurs on one side of the encoding, caused by an index representing the predicted motion vector, a small amount of calculation when performing inter-prediction in the second mode of operation is small on the one hand of decoding.

[000216] For example, in a third inter-prediction operation mode, pixels 1705 at a predetermined location in the current encoding unit 1700 are compared to pixels 1715, 1725, 1735 at the predetermined locations in neighboring encoding units A, B and C 1710, 1720 and 1730, pixels, the degrees of distortion of which are lowest are detected between pixels 1715, 1725, 1735, and a motion vector from a neighboring encoding unit including the detected pixels is selected as a vector of predicted motion of the current 1700 coding unit.

[000217] So, although a amount of calculation may be large for the decoding side to detect pixels,

77/93 the degrees of distortion of which are the lowest, the coding side does not experience extra code in bits to be transmitted. In particular, if inter-prediction is performed on a sequence of images including a specific image pattern in the third mode of operation, a prediction result is more accurate than when an average value of motion vectors from neighboring coding units is used.

[000218] The video encoding device 1400 can encode information regarding a relationship between the first mode of operation, the second mode of operation, and the third mode of inter-prediction operation determined according to a depth of a unit of coding. The video decoding apparatus 1500 according to an exemplary mode can decode the image data by extracting information regarding a first mode of operation, the second mode of operation and the third mode of inter-prediction operation determined according to the depth of the coding unit, from a received bit stream, and perform a decoding tool related to motion compensation and inter-prediction performed on a current coding unit of a coded depth, based on the extracted information.

[000219] The video encoding device 1400 checks whether extra code occurs in bits to be transmitted in order to determine an inter-prediction mode of operation according to a size or depth of an encoding unit. If a small coding unit is coded, additional extra code can greatly decrease its coding efficiency, whereas if a large coding unit is coded, a coding efficiency is not

78/93 significantly influenced by additional extra code. [000220] Consequently, it may be efficient to perform interpretation in the third mode of operation that does not cause additional extra code when a small coding unit is coded. In this regard, an example of a relationship between the size of a coding unit and an inter-prediction mode of operation is shown in Table 3 below:

Table 3

Size of unity of encoding = 4 Size of unity of encoding = 8 Size of unity of encoding = 16 Size of unity of encoding = 32 Size of unity of encoding = 64 Inter-prediction operation mode third mode of operation third mode of operation first mode of operation second mode of operation second mode of operation

[000221] Figure 20 is a diagram to describe a relationship between a depth of a coding unit, a coding tool (for example, intra-prediction), and a mode of operation, according to an exemplary modality.

[000222] A video encoding device 1400 according to an exemplary modality can perform directional extrapolation as intra-prediction by using reconstructed pixels 1810 neighbors to a current encoding unit 1800. For example, an intra-prediction direction can be defined as tan ^_1 (dx, dy), and inter-prediction can be performed in several directions according to a plurality of parameters (dx, dy).

[000223] A neighboring pixel 1830 in a line extending from a current pixel 1820 in the current coding unit 1800, which must be predicted, and being tilted at an angle of tan ^_1 (dx, dy) determined by dx values and dy from the current pixel 1820, can be used as a predictor of the current pixel 1830. The neighboring pixel 1830 can belong to a unit of

79/93 encoding which is located on an upper or left side of the current 1800 encoding unit, which was previously encoded and reconstructed.

[000224] If intra prediction is performed, the video encoding device 1400 can adjust a number of intra prediction directions according to the size of an encoding unit. Thus, intra-prediction modes of operation, which is a type of coding tool, can be classified according to the number of intra-prediction directions.

[000225] A number of intra-prediction directions may vary according to the size and structure of the hierarchical tree of

one unit in coding. Bits of code extra used for represent one intra-mode -prediction can decrease The efficiency in coding in a little unity in coding, but do not affect an efficiency coding in

a large coding unit.

[000226] Thus, the video encoding device 1400 can encode information regarding a relationship between a depth of an encoding unit and the number of intra-prediction directions. In addition, a video decoding device 1500 according to an exemplary embodiment can decode image data by extracting information regarding a relationship between a depth of the encoding unit and the number of intrapredictive directions from a bit stream. received, and perform a decoding tool related to intra-prediction performed on a current coding unit of a coded depth, based on the extracted information.

[000227] The video encoding device 1400 considers it a

80/93 image standard of the current coding unit in order to determine an intra-prediction mode of operation according to the size or depth of a coding unit. In the case of an image containing detailed components, intraprediction can be performed using linear extrapolation, and thus, a large number of intraprediction directions can be used. However, in the case of a flat region of an image, the number of intra-prediction directions can be relatively small. For example, a simple mode or a bilinear mode using interpellation or neighboring reconstructed pixels can be used to perform intra-prediction on a flat region of an image.

[000228] Since a large coding unit is likely to be determined in a flat region of an image, the number of intra-prediction directions can be relatively small when an intra-prediction mode is performed on the large coding unit. In addition, since a small coding unit is likely to be determined in a region including detailed components of an image, the number of intra-prediction directions can be relatively large when the intra-prediction mode is performed on the small coding unit. Thus, a relationship between the size of a coding unit and the intra-prediction mode can be considered as a relationship between the size of the coding unit and the number of intra-prediction directions. An example of the relationship between the size of the coding unit and the number of intra-prediction directions is shown in Table 4 below:

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Table 4

Size of unity of encoding = 4 Size of unity of encoding = 8 Size of unity of encoding = 16 Size of unity of encoding = 32 Size of unity of encoding = 64 Number of intra-prediction directions 9 9 33 17 5

[000229] A large coding unit can include image patterns that are arranged in several directions, and intra-prediction can thus be performed on the large coding unit using linear extrapolation. In this case, a relationship between the size of a coding unit and the intra-prediction mode can be established as shown in Table 5 below:

Table 5

Size of unity of encoding = 4 Size of unity of encoding = 8 Size of unity of encoding = 16 Size of unity of encoding = 32 Size of unity of encoding = 64 Number of intra-prediction directions 9 9 33 33 17

[000230] According to an exemplary modality, the prediction coding is carried out in various intra prediction modes established according to the sizes of the coding units, thereby more efficiently compressing an image according to the characteristics of the image.

[000231] Predicted encoding units emitted from the video encoding apparatus 1400 by carrying out various modes of intra-prediction according to the depths of the encoding units have a predetermined directionality according to the type of an intra-prediction mode. prediction. Due to a directionality in such predicted coding units, a prediction efficiency

82/93 can be high when the pixels of a current encoding unit that are to be encoded have a predetermined directionality, and can be low when the pixels of the current encoding unit are not predetermined in orientation. Thus, a predicted coding unit obtained using intra-prediction can be post-processed by producing a new predicted coding unit by changing pixel values in the predicted coding unit using these pixels and at least one neighboring pixel, thereby improving the image prediction efficiency.

[000232] For example, in the case of a flat region of an image, it may be efficient to perform post-processing to smooth out a predicted coding unit obtained using intra-prediction. In addition, in the case of a region having detailed image components, it may be efficient to perform post-processing to maintain the detailed components in a predicted coding unit obtained using intra-prediction.

[000233] Thus, the video encoding device 1400 can encode information regarding a relationship between a depth of an encoding unit and an operating mode indicating whether a predicted encoding unit obtained using intra-prediction should be post-processed. In addition, the video decoding apparatus 1500 can decode image data by extracting information regarding the relationship between a depth of a coding unit and an operating mode indicating whether a predicted coding unit obtained using intra-prediction should be post-processed, from a stream of received bits, and

83/93 perform a decoding tool related to intraprediction executed in a current coding unit of a coded depth, based on the extracted information.

[000234] In the video encoding device 1400, an intra-prediction mode, in which post-processing for smoothing is performed and an intra-prediction mode in which post-processing for smoothing is not performed, can be selected for a flat region of an image and a region including detailed components of the image, respectively, such as the mode of operation indicating whether a predicted coding unit obtained using intra-prediction should be post-processed.

[000235] A large coding unit can be determined in a flat region of an image and a small coding unit can be determined in a region containing detailed components of the image. Thus, the video encoding apparatus 1400 can determine that an intra-prediction mode, in which post-processing for smoothing is performed, is performed on a large coding unit and an intra-prediction mode, in which post-processing for smoothing it is not performed, it is performed on the small coding unit.

[000236] Consequently, a relationship between a depth of a coding unit and a mode of operation indicating whether a predicted coding unit obtained by intraprediction should be post-processed can be considered as a relation between the size of a coding unit and whether post-processing should be performed. In this regard, an example of a relationship between the size of a coding unit and an intra-prediction mode of operation can be

84/93 shown in Table 6 below:

Table 6

Size of unity of encoding = 4 Size of unity of encoding = B Size of unity of encoding = 16 Size of unity of encoding = 32 Size of unity of encoding = 64 Intra-prediction post-processing mode 0 0 1 1 1

[000237] If the video encoding device 1400 performs transformation, which is a type of encoding tool, rotational transformation can be selectively performed according to an image pattern. For efficient rotation transformation calculation, a data matrix for rotational transformation can be stored in memory. If the video encoding device 1400 performs rotational transformation or if the video decoding device 1500 performs reverse rotational transformation, related data can be called up from memory using a rotational transformation data index used for the calculation. Such rotational transformation data can be established in coding units or transformation units, or according to the type of a sequence.

[000238] Thus, the video encoding apparatus 1400 can establish a transformation mode indicated by an index of a rotational transformation matrix corresponding to a depth of a coding unit as a transformation operation mode. The video encoding apparatus 1400 can encode information regarding a relationship between the size of an encoding unit and the transformation mode indicating the index of the rotational transformation matrix.

85/93 [000239] The video decoding device 1500 can decode the image data by extracting information regarding the relationship between a depth of a coding unit and the transformation mode indicating the index of the rotational transformation matrix from a received bit stream, and perform reverse rotational transformation into a current coding unit of an encoded depth, based on the extracted information.

[000240] Consequently, a relationship between a depth of a coding unit, rotational transformation, and a mode of operation can be considered as a relationship between the size of a coding unit and the index of the rotational transformation matrix. In this respect, a relationship between the size of a coding unit and a rotational transformation mode of operation can be shown in Table 7 below:

Table 7

Size of unity of encoding = 4 Size of unity of encoding = 8 Size of unity of encoding = 16 Size of unity of coding - 32 Size of unity of encoding = 64 rotational transformation matrix index 4-7 4-7 0-3 0-3 0-3

[000241] If the video encoding device 1400 performs quantization, which is a type of encoding tool, a delta quantization parameter representing a difference between a current quantization parameter and a predetermined representative quantization parameter can be used. The delta quantization parameter can vary according to the size of a coding unit. Thus, in the video encoding device 1400, a quantization operation mode

86/93 can include a quantization mode indicating whether the delta quantization parameter varying according to the size of a coding unit should be used.

[000242] Thus, the video encoding device 1400 can establish a quantization mode indicating whether the delta quantization parameter corresponding to the size of an encoding unit should be used as a quantization operation mode. The video encoding apparatus 1400 can encode information regarding a relationship between a depth of an encoding unit and the quantization mode indicating whether the delta quantization parameter should be used.

[000243] The video decoding device 1500 can decode the image data by extracting information regarding the relationship between a depth of a coding unit and the quantization mode indicating whether the delta quantization parameter should be used, starting from a received bit stream, and perform reverse quantization in a current coding unit of an encoded depth, based on the extracted information.

[000244] Consequently, a relationship between a depth of a coding unit, quantization, and a mode of operation can be considered as a relationship between the size of a coding unit and whether the delta quantization parameter should be used. In this regard, an example of a relationship between the size of a coding unit and a mode of quantization operation is as shown in Table 8 below:

87/93

Table 8

Size of unity of encoding = 4 Size of unity of encoding = 8 Size of unity of encoding = 16 Size of unity of encoding = 32 Size of unity of encoding = 64 Parameter of delta quantization false false false false false

[000245] Figure 21 illustrates the syntax of a set of sequence parameters 1900, in which information regarding a relationship between a depth of a coding unit, a coding tool, and an operating mode, is inserted according to an exemplary modality.

[000246] In Figure 21, sequence_parameter_set denotes the syntax of the sequence parameter set 1900 for a current slice. Referring to Figure 21, information regarding the relationship between a depth of a coding unit, a coding tool, and an operating mode is inserted into the syntax of the sequence parameter set 1900 for the current slice.

[000247] Furthermore, in Figure 21, picture_width denotes the width of an inserted image, picture_height denotes the height of the introduced image, max_coding_unit_size denotes the size of a maximum encoding unit, and max_coding_unit_depth denotes a maximum depth.

[000248] According to an exemplary modality, syntaxes use independent cu_decode_flag indicating whether decoding should be performed independently in coding units, use_independent_cu_parse_flag indicating whether analysis should be performed independently in coding units, use_mv_accuracy_control_flag indicating whether a motion vector should be controlled exactly, use_arbitrary_direction_intra_flag indicating whether intra-prediction

88/93 should be performed in an arbitrary direction, use_frequency_domain_prediction_flag indicating whether prediction encoding / decoding should be performed in a frequency transformation domain, use_rotational_transform_flag indicating whether rotational transformation should be performed, use_tree_significant_map_flag indicating whether encoding / decoding should be performed using a significant tree map, use_multi_parameter__intra_prediction_f lag indicating whether intra-prediction coding should be performed using multiple parameters, use_advanced_motion_vector_prediction_flag indicating whether advanced motion vector prediction should be used, use_adaptive_loop_filter_flag indicating whether adaptive loop filtering must be used_adaptive_adaptive_filter_filter_filter adaptive loop of four branches tree should be performed, use_delta_qp_flag indicating if quantization should be performed using using a delta quantization parameter, use_random_noise_generation_flag indicating whether random noise generation should be performed, use_asymmetric_motion_partition_flag indicating whether motion estimation should be performed in asymmetric prediction units, can be used as examples of a slice sequence parameter. It is possible to efficiently encode or decode the current slice by establishing whether the above operations should be used using these syntaxes.

[000249] In particular, the length of an adaptive loop filter alf_filter_length, the type of the loop filter

89/93 adaptive alf_filter_type, a reference value for quantizing an adaptive loop filter coefficient

alf_qbits, and the number of components of color of filtration in adaptive loop alf_num_ color can be established at the set of parameters of sequence 1900, based in use_adaptive_ loop_filter_flag and use_quadtree_ adaptive_loop _f ilter_flag. [000250] A information regarding relationship in between an

depth of an encoding unit, an encoding tool, and an operating mode used in a 1400 video encoding apparatus and a 1500 video decoding apparatus according to the exemplary modalities may indicate an inter-prediction operating mode corresponding to a depth of a uiDepth mvp_mode [uiDepth] encoding unit, and a significant_map_mode [uiDepth] mode of operation indicating the type of a significant map among significant tree maps. That is, a relationship between inter-prediction and a corresponding mode of operation according to a depth of a coding unit, or a relationship between coding / decoding using the significant tree map, and a corresponding mode of operation according to a depth of a coding unit, can be set in the sequence parameter set 1900.

[000251] A bit depth of an input sample input sample_bit_depth and a bit depth of an internal sample internal_sample_bit_depth can also be set in the sequence parameter set 1900.

[000252] Information regarding a relationship between a depth of a coding unit, a tool for

90/93 encoding, and an operating mode encoded by the video encoding device 1400 or decoded by the video decoding device 1500 according to an exemplary embodiment is not limited to the information entered in the set of sequence parameters 1900 illustrated in Figure 21 For example, information can be encoded or decoded into maximum encoding units, slice units, frame units, image units, or GOP units of the image.

[000253] Figure 22 is a flow chart illustrating a video encoding method based on an encoding tool considering a size of an encoding unit, according to an exemplary modality. With reference to Figure 22, in operation 2010, a current image is divided into at least one maximum coding unit.

[000254] In operation 2020, a coded depth is determined by coding at least one maximum coding unit in coding units corresponding to the depths in the operating modes of the coding tools, respectively, based on a relationship between a steel depth least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode. So, at least one

unity in maximum coding includes coding units corresponding to at least an depth coded. [000255] THE relationship between an depth at least an unity in coding gives at least one unit in

Maximum encoding, an encoding tool, and an operating mode can be preset in units of slices, frames, GOPs, or frame sequences of an image. The relationship between a depth of at least one unit of

91/93 coding of at least one maximum coding unit, a coding tool, and an operating mode can be determined by comparing the coding results of the coding units corresponding to the depths in at least one operating mode equating coding tools each other, and selecting an operating mode having a higher coding efficiency from at least one operating mode during the coding of at least one maximum coding unit. Otherwise, the relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode, can be determined in such a way that coding units corresponding to the depths, whose sizes are less than or equal to a predetermined size, can correspond to a mode of operation that does not cause bits of extra code to be inserted into an encoded data stream and to the other encoding units, whose sizes are larger than the predetermined size, can correspond to an operating mode causing bits of extra code.

[000256] In operation 2030, a bit stream including encoded video data of at least one encoded depth, information pertaining to encoding, and information pertaining to the relationship between a depth of at least one encoding unit of at least one encoding unit maximum, a coding tool, and an operating mode in at least one maximum coding unit is produced. Coding information can include at least one coded depth and information regarding a coding mode in at least one coding unit

Maximum 92/93. Information regarding the relationship between a depth of at least one coding unit of at least one maximum coding unit, a coding tool, and an operating mode, can be entered in slice units, frame units, GOPs, or sequences of the image.

[000257] Figure 23 is a flowchart illustrating a method of decoding video based on an encoding tool considering an encoding unit size, according to an exemplary modality. Referring to Figure 23, in operation 2110, a bit stream including encoded video data is received and analyzed.

[000258] In operation 2120, encoded video data, encoding information, and information relating to a relationship between a depth of an encoding unit, an encoding tool, and an operating mode are extracted from the flow of bits. Information regarding a relationship between a depth of a coding unit, a coding tool, and an operating mode can be extracted from the bit stream in maximum coding units, slice units, frame units, GOP units , or frame sequences of an image.

[000259] In operation 2130, encoded video data is decoded into maximum encoding units according to an encoding tool operating mode equating to an encoding unit corresponding to at least one encoded depth, based on the information relating to the coding and information regarding a relationship between a depth of a coding unit, a coding tool, and a mode of operation, extracted from

93/93 from the bit stream.

[000260] Although not limited to this, one or more exemplary modalities can be recorded as computer programs and can be implemented on computers in common use that execute the programs using a computer-readable recording medium. Examples of the computer-readable recording medium include magnetic storage media (for example, ROM, floppy disks, hard drives, etc.) and optical recording media (for example, CD-ROMs or DVDs). In addition, although not required in all exemplary embodiments, one or more units of the video encoding apparatus 100 or 1400, video decoding apparatus 200 or 1500, image encoder 400, and image decoder 500 may include a processor or microprocessor running a computer program stored in a computer-readable medium.

[000261] Although exemplary modalities have been particularly shown and described with reference to the drawings above, it will be understood by those of ordinary skill in the art that various changes in shape and details can be made here without departing from the essence and scope of the invention as defined by attached claims. Exemplary modalities should be considered only in the descriptive sense and not for the purpose of limitation. Therefore, the scope of the invention is defined not by the detailed description of the invention, but by the appended claims, and any differences within the scope will be considered to be included in the present invention.

Claims (2)

- CLAIMS 1. METHOD OF DECODING VIDEO DATA, the method characterized by comprising: dividing an image into several encoding units (2110); and obtaining, from a received bit stream, information about a relationship between depth of a coding unit and a quantization mode, wherein information about the relationship between a depth of a coding unit and a quantization mode, in which the information about the said relationship indicates a quantization mode, for each depth between a plurality of depths, I indicates whether a delta quantization parameter of the respective depth should be used (2120), where: the image is divided into a plurality of maximum coding units, a maximum coding unit, among the plurality of maximum coding units, is hierarchically divided into one or more depth coding units including at least one of the current depth and one lower depth according to the coding units division information, where the coding units division information is obtained from the bit stream: additionally comprising, for a current depth coding unit: determine whether the delta quantization parameter should be used in the current depth coding unit, based on information about the said relationship (2130); Petition 870190086982, of 9/5/2019, p. 4/45 2/2 when the division information indicates a division for the current depth, the coding unit for a current depth is divided into four coding units for the lower depth, regardless of the neighboring coding units, and when the division information for the unit current depth coding indicates a non-division, one or more transformation units are obtained from the current depth coding unit by dividing the current depth coding unit using transformation unit division information obtained from the flow bits, and inverse quantization is performed on one or more transformation units using the result of determining whether the delta quantization parameter should be used in the current depth coding unit.